This invention relates to devices for applying texture material to surfaces, and more particularly to such devices having a spring-loaded trigger where it is desired to maintain the trigger in a consistent position during application.
A variety of devices are available for applying texture material to surfaces, such as the wall and ceiling of a building. While such material could be applied using manual tools, manual application generally does not provide a desired consistent pattern of material. Accordingly, automated tools have been developed to direct a consistent stream or spray of texture material at a desired surface. Such devices have been constructed in the general design of a spray gun having a mechanical trigger which the operator holds in a predetermined position to cause the gun to emit the texture material.
A problem with the existing spray gun devices is excessive operator discomfort and fatigue due to the need to maintain the trigger in an "on" position. A resilient member, such as a spring, is typically provided to urge the trigger to the "off" position whenever the operator is not actively holding it in the "on" position. This eliminates the need for the operator to actively move the trigger into the "off" position.
In order to provide sufficient force to move the trigger to the "off" position, the resilient member selected in these applications is relatively stiff. As a result, when moving the trigger levers of the prior art devices to the "on" position, the operator must provide a substantial amount of force to overcome the resilient member, and the operator must continue to provide this force as long as he desires to apply the texture material. Because applicator devices of this type are generally designed for use by tradespeople in the construction industry for large areas, many operators use the devices for extended periods of time. The need to apply substantial force to the trigger lever for extended periods causes discomfort and fatigue to the operators.
One solution to this problem might be to employ a resilient member having less stiffness in order to reduce the amount of force that an operator must supply to move the trigger member into the "on" position and maintain it there. However, reducing the stiffness of the resilient member enough to substantially reduce operator fatigue results in insufficient force from the resilient member to return the trigger to the "off" position upon release by the operator.